Bursae are thin, sac-like, fluid-filled structures which are enclosed by synovium and are commonly located between muscles to reduce friction as they glide over each other or on top of prominent bony protrusions to facilitate the movement of muscle or tendon across these structures or to protect them from direct trauma. Bursitis, or irritation of these structures, can result from inflammatory or noninflammatory processes. Common causes of bursitis include direct trauma, prolonged pressure, overuse or highly intensive activity, infection, and gout or inflammatory arthritis. Aspiration and laboratory analysis of the bursal fluid is indicated in cases where septic, gouty, or inflammatory bursitis is suspected. Imaging is typically not required though with deeper bursae, concern for alternative pathology, or to guide aspiration/injection, magnetic resonance imaging (MRI) or ultrasound may be helpful.